Method and apparatus for making permanently sealed resilient insulation



Sept. 14, 1965 c. A. STICKEL METHOD AND APPARATUS FOR MAKING PERMANENTLYSEALED RESILIENT INSULATION 5 Sheets-Sheet 1 Filed Dec. 18, 1961 n9 QQAQ/ o INVENTOR p 14, 1965 c. A. STICKEL 3,206,345

METHOD AND APPARATUS FOR MAKING PERMANENTLY SEALED RESILIENT INSULATIONFiled Dec. 18, 1961 5 Sheets-Sheet 2 INVEN TOR.

Sept. 14, 1965 c. A. STICKEL 3,206,345

METHOD AND APPARATUS FOR MAKING PERMANENTLY SEALED RESILIENT INSULATIONFiled Dec. 18, 1961 3 Sheets-Sheet 5 F EL/,8

United States Patent 3,206,345 METHOD AND APPARATUS FGR MAKING PER-MANENTLY SEALED RESILIENT INSULATIQN Carl A. Sticlrel, Dayton, Uhio,assignor to General Motors Corporation, Detroit, Mich, a corporation ofDelaware Filed Dec. 18, 1961, Ser. No. 160,009 14 Claims. (Cl. 156'145)This invention relates to improved insulating means and moreparticularly to a method of and apparatus for replacing the air in theresilient insulation with the gas having better insulating propertiesand permanently sealing in the gas.

It has been recognized that certain gases with inherently lowcoeflicients of heat transmission after displacing air from insulatingmaterials will substantially increase the insulating properties of goodinsulating material such as glass fibers or mineral wool. However, ithas been diflicult to provide a simple rapid inexpensive method of andapparatus for permanently enclosing such gases in the glass fibers ormineral wool. It has also been difficult to prevent the leakage of suchgases and to prevent the puncturing of the enclosure during theprocessing of the insulation and during the handling of it afterward.Various means have often been proposed for accommodating the expansionand contraction of the gas during extreme changes in temperature andalso in barometric pressure.

It is an object of my invention to provide a simple rapid reliableinexpensive process and apparatus for making a permanently sealedresilient insulation containing a gas having a low coefficient of heattransmission.

It is another object of my invention to provide a simple rapid reliableinexpensive process and apparatus for squeezing air out of resilientinsulation and replacing the air with the gas having a lower coefiicientof heat transmission and also enclosing and sealing the gas in theresilient insulation.

It is another object of my invention to provide a simple improved meanshaving high insulating value for protecting the enclosure of the sealedresilient insulation from puncture and leakage during processing andsubsequent handling and also to accommodate the expansion andcontraction of the gas sealed therein.

These and other objects are attained in the first form in which twospaced parallel conveyer belts have applied to their interior faces athermoplastic film and a protective strip which are fed thereon at thespeedof the conveyer belts. From a roll, pieces of glass fibers ormineral wool are cut and deposited between the protective stripin-between the conveyer belts for feeding to the point where a squeezingroll cooperates with one of the belts to squeeze a gas such as the airout of the resilient insulation. After the material is squeezed by thesqueezing roll, the edges of the film are heat sealed on the oppositesides of the resilient insulating material. The gas having the lowcoefficient of heat transmission is piped into the interior in-betweenthe two sheets or strips of thermoplastic film beyond the point of heatsealing so that as the resilient insulating material reexpands it isfilled with this gas. Beyond this point the film in-between the piecesor slabs of the resilient insulation is transversely heat sealed to forma bag by applying flying heat sealing devices extending transverselyacross the material and move with the material as this is done.Following this point, there is sprayed onto the entire exterior amixture of materials which will form a closed cell substantiallyimpervious resilient foamed polymer preferably also containing a gashaving a low coeflicient of heat transmission. Infrared heaters quicklycomplete the foaming and curing of this foam polymer and at the nextstation the slabs are separated by flying cutters which as the movementof the 3,296,345 Patented Sept. 14, 1965 "ice material continues cut thematerial in-between the air heat sealed transverse closing to completethe insulation package.

In the second form of the invention, the resilient material is fedin-between squeezing rollers into an enclosed chamber having itsatmosphere made up entirely of the gas with the low coefficient of heattransmission. Within this chamber after passing through the squeezingrollers, the exterior of the material is coated with a mixture ofmaterials forming a substantially closed cell substantially imperviousflexible foamed polymer preferably containing a gas having a lowcoefiicient of heat transmission; This mixture is foamed and cured underthe application of infrared heat. A cutting device controlled by anelectric eye cuts the coated material into slabs which are caught belowand held while the edges are sprayed with the similar mixture ofmaterials forming a substantially closed cell substantially imperviousflexible foam polymer containing the same gas having the low coefficientof heat transmission. These materials are foamed and cured under theapplication of infrared heat after which the completed slabs passthrough a double door sealing arrangement out of the enclosurecontaining the gas atmospherc.

Further objects and advantages of the presentinvention will be apparentfrom the following description, ref.- erence being bad to theaccompanying drawings wherein preferred embodiments of the presentinvention are clear- 1y shown.

In the drawings:

FIGURE 1 is a diagrammatic view of the first form apparatus embodying myinvention;

FIGURE 2 is an enlarged fragmentary view taken in the direction of thearrow 2 on FIGURE 1;

FIGURE 3 is an enlarged tranverse sectional view taken along the line 33of FIGURE 1;

FIGURE 4 is an enlarged transverse sectional view taken alongthe line4--4 of FIGURE 1;

FIGURE 5 is an enlarged transverse sectional view taken along the line55 of FIGURE 1;

FIGURE 6 is a diagrammatic view of the second form of my invention and;

FIGURE 7 is an enlarged sectional view taken along the line 7-7 of thecompleted insulation produced by the apparatus shown in FIGURE 6.

Referring now to the diagrammatic illustration FIG- URES 1 and 2 thereis shown a large supply roll 20 provided with a long strip of suitablepervious insulating material such as glass fibers, mineral wool or anopen cell foam elastomer. The strip 22 of one of these materials comesoff the roll 20 over an idler roller 24 between two feed rollers 26. Thefeed rollers 26 are driven by an electric motor 28 through the controlsystem 30. The feed rollers 26 are synchronized with the control system30 so that at the proper time the cutters 32 are operated to cut off thestrip 22 into pieces 34 of the length desired. The pieces 34 aredeposited upon the lower conveyor belt 36 which passes around a largedrive roller 38 and a squeezing roller 40 as well as idler rollers 42,44, 46 and a series of idler rollers designated by reference character48a The belt 36 is driven at a faster rate than the supply provided bythe feed rollers 26 so that the pieces 34' are spaced a desired uniformamount upon the belt 36.

The upper face of the belt 36 is covered by a thin thermoplastic film orsheet 50 which comes off the feed roll 52. and extends over the surfaceof the belt 36. This film is preferably made up of one or more layers ofvinylidene chloride sheet. However, if desired other forms of heatsealable plastic film or sheet such as vinyl chloride acetate sheet or acopolymer of vinyl chloride and vinylidene chloride or a polyester ofetheleneglycol and tereph-thalic acid. With some glass fiber and mineralaaoasae in? wool, there is a possibility that some sharp nedle-likepiece may puncture the film 56. In order to avoid this possibility ofpuncturing, providing such materials are used, I provide a roll 54 ofthin open cell foam elastomeric sheeting or kraft paper 56 which is;narrower than the film and of substantially the same'width as the glassfibers or mineral wool 22. From this roll 54 a strip 56 is laid over thefilm 50 on the belt 36. The pieces 34 of insulation rest on top of thestrip 56 in spaced relation as shown in FIGURES 1 and 3.

A second roll 58 lays a strip of material or sheeting 60 on top of thepieces 34. This second roll 58 and its strip 60 are similar or identicalto the roll 54 and the strip 56. Thus the pieces 34 are between thesheeting 56 and 66. On top of the sheeting 60 thereis supplied a film 62of thermoplastic film which comes off the supply roll 64. The supplyroll 64 and the film 62 may be similar to or identical to the roll 52and film 50.. The film 62 and the sheeting 60 are applied to the tops ofthe insulation pieces 34 by an upper belt 66 which is driven by a smalldrive roller 68 and passes around the idler rollers 70 and 72. Both thebelts 36 and 66 are endless and hold the insulation pieces 34 in spacedrelation as long as they are in contact with the belts.

The belts 36 and 66 thus apply the film 50 and 62 as well as thesheeting 56 and 60 to the opposite flat sides of the insulation pieces34. The drive rollers 38 and 68 for the belts 36 and 66 are driven by anelectric motor 74 through transmission means 76 at identical linearspeeds. The squeezing roller 40 and the adjacent portion of the beltcooperate with the cooperating squeezing roller 78 also driven by themotor 74 at a surface speed equal to that of the belts 36 and 66. Theroller 7 8 has a resilient surface of foamed or solid elastomer.

As shown a gas such as the air is being squeezed out of one of theinsulation pieces 80 by pressing together the films 62 and 50. Theassemblies of the insulation piece, the sheeting, and the films continuebetween additional sets of squeezing rollers 32 and 84 having resilientflanges 86 and 88 of elastomeric material which hold together the edgesof the film. These squeezing rollers 82 and 84 also have resilientsurfaces of foamed or solid elastomer. These rollers 82, 84substantially complete the pressing of the air out of the insulationpiecessuch as the piece 80 and also prevent any re-entry of air bykeeping the edges of the films 50 and 62 pressed together. The gas suchas air Within the insulation pieces 34 between the film 50 and 62 isreplaced by a gas having a low co-eflicient of heat transmission such asdifluorodichloromethane or sulphur dioxide. This gas is supplied from asupply tank or other source 90 through a shut off valve 92 and piping 94under the control of a pressure in the two supply pipes 98 which extendbetween the ends of the rollers 88 and the nearest edge heat sealingrollers 121 located upon opposite sides of each edge of the two sheetsof film 62 and 50. Each of the two supply pipes 98 has its end portionextending inwardly between the two sheets of film 50 and 62 and isturned at right angles in the direction of movement as shown in FIG. 2to provide the outlet 123 within the sealed enclosure provided bysealing the edges of the film 50 and 62. Additional heat sealing andpressing rollers 125 and 127 are provided to insure the proper sealingof the edges of the film so as to prevent the egress of air and theescape of the gas having a lower coeflicient of heat transfer. Therollers 84 are preferably spring pressed together so as to exclude andpress out substantially all of the air. Preferably they are independentof or have a resilient connection with the flanges 88 so thatsubsantially all the air will be squeezed out.

Below the rollers 127 the films in-between the pieces 34 of insulationare sealed together by a set of flying transverse heat sealers 129 and131. These transversely seal the film in the space provided between eachadjacent piece 34 of the insulation so as to provide a transverse sealateach end of each piece 34 which cooperates with the seals on each sideto constitute a completed bag or sheet enclosure. This makes it possibleto fill the insulation space pieces 34 and the entire enclosure betweenthe film 50 and 62 with the gas from the supply source 96. These heatsealers 129 and 131 are mounted upon a movable frame 133 which isreciprocated through the connecting rod 135 and eccentric drive 137driven through the transmission 139 also by the electric motor 74. Theheat sealers 129 and 131. are moved into position when the frame 133 ismoving with the films 511 and 62 by the air cylinders 141 and 143mounted upon the framework 133 and connected by the pipes 145 and 147 tothe supply and exhaust air pressure pipes 149 and 151 which extend fromthe control valve of 153 having an actuator 155 which is operated byprojections 157 and 159 upon the eccentric drive 137 so that the aircylinders 141 and 143 are operated at the exact time that the movementof the frame 133 is synchronized with the movement of the film 50 and62.

Below the heat sealers 131 the entire outer surface of the film 5t) and62 enclosing the pieces 34 is sprayed from the spray nozzles 161 and 163with a mixture of materials forming a flexible closed cell foam polymerpreferably containing in the cells a gas having a low coefficient ofheat transmission. Preferably the foam is of the polyurethane type. Asone specific example of materials forming a flexible closed cellsubstantially impervious foam polymer there is supplied through theconduit 165 the component A in parts by weight consisting of a mixtureof 44 parts of toluene diisocyanate and 15 parts by weight ofmonofluorotrichloromethane. The toluene diisocyanate consists of amixture of 80 parts of 2,4 toluene diisocyanate and 20 parts of 2,6toluene diisocyanate. For the second resin component B supplied throughthe conduit 167 there is provided a mixture in 90 parts by weightconsisting of parts of castor oil, 10 parts by weight of distilled talloil and 3 catalysts including /2 part of n ethyl morpholene, .2 partstannous octoate, 1.0 part of tetramethylguanidine. The resin componentalso includes surfactant in the amount of 1.5 parts of organosiloxane.This resin component B is supplied through the conduit 167 to the mixer169 for supply through the conduit 171 to the spray heads 161 and 163which spray the entire outer surface of the films 62 and 50 with thecomponents which form the flexible closed cell substantially imperviousfoam polymer directly adherent to the film to provide a resilientprotective coating for the film. The foaming of the components continuesunder the heat provided by the infrared heaters 173 and 175 provided onopposite sides of the insulation assembly. This heat also cures the foamwhich provides a complete protective enclosure 1'77 (FIG. 5) completelyaround the films 50 and 62. The foam protects the film 50, 62 from beingpunctured by external means and in addition seals the film to furtherprevent the escape of the gas therein having a low coefficient of heattransmission and also to prevent the ingress of air thereto. Inaddition, it can be cornpressed and can expand to accommodate changes intemperature and atmospheric pressure. The frame 133 also carries theflying transverse cutters 179 which are spaced a proper distance awayfrom the heat sealers 129 and 131 so that the insulation is cutin-between the two heat sealing areas produced by the heat sealers 129and 131 but spaced one insulation piece 34 below the heat sealers. Theseflying cutters 179 are synchronized in movement with the movement of thefilm 51), 62 when they are actuated by the air cylinder 181 also underthe control of the valve 153. After being cut, the completed insulation183 drops onto a conveyor belt (not shown) for transmission to storageor a place of use.

In the second form of the invention the strip of glass fiber or mineralwool or open cell foam 220 is fed from a supply roll 222. It is drawnbetween two sets of squeezing rolls 224 and 226 preferably havingsurfaces of a foamed or solid elastomer. One of the rolls 224 is drivenby electric motor 228 which if desired may drive all of the squeezingrollers. The rollers 224 are placed at the entrance of a large enclosedchamber 230 closed by a wall 232. The seals 234 are provided between thewall 232 and the rollers 224 to prevent the escape of the gas within thechamber 230. The rollers 224 and 226 preferably are spring pressedtogether to squeeze substantially all of the air out of the strip ofpervious or permeable resilient insulation 220. This material expandswithin the chamber 236 after it passes the rolls 226 and thereby allowsthe gas within the chamber 230 to penetrate it and fill its voids. Thegas supplied from the supply tank 347 preferably is a gas having a lowcoefiicient of heat transfer and preferably is the same gas as suppliedfrom the tank 90 in the first embodiment. In this second form no film orbag is used to enclose the insulation.

Instead the components forming the resilient closed cell substantiallyimpervious foamed polymer are sprayed directly onto the strip ofresilient insulation material 220 after it has absorbed the gas in thechamber 230 and after it has fully reexpanded. This is accomplished bythe spray heads 236 and 238 which are supplied from the mixer 246. Themixer 240 is supplied through the conduit 242 with the component A andthrough the conduit 244 with the resin component B in the sameproportions as supplied to the mixer 169 in FIGURE 1. As the strip 220moves downwardly as it is fed by the squeezing rollers 224, its sidesand edges are sprayed with the components issuing from the spray heads236 and 238 onto its sides and edges to provide a complete flexible foamenclosure for the strip 220.

The foam materials are heated and cured by infrared heat from theinfrared heaters 246 and 248 which surround the strip 220 below thespray heads 236 and 238. At a lower level within the chamber 230 thereis provided a spotlight 250 which normally sends a beam of light 252onto the photocell 254. Whenever the strip 220 moves far enoughdownwardly to intercept the light beam 252, the photocell 254 initiatesthe operation of a timer control 256 which controls the air cylinders258 and 260 to withdraw the framework 262 to the left through theirconnections with the floating lever 264 providing the connection betweenthe pistons in the cylinders 258 and 260 with the framework 262. Thecylinders 258 and 266 are controlled by the valves 266 and 268 which arepreferably of the solenoid type which in turn are controlled by thetimer 256. The valve 270 controls the air cylinder 272 which in turnprojects the stop 274 to the left beneath the strip 220. The timer 256then controls the solenoid valve 276 to operate the air cylinder 278which in turn operates the cutters 280 and 282 which cut the insulationstrip 220 to the proper length.

At the same time the timer 256 operates the solenoid valve 284 tocontrol the pistons in the air cylinders 286 and 288 to retract theholding plates 290 and 292 away from each other a sufiicient distance toallow the piece of insulation 294 which is cut at the same time by thecutter 280 to drop into position between the plates 292 and 290 and isheld upon the stop 274. The timer 256 then operates cylinders 286 and288 to move the plates 292 and 290 into position in which it holds theinsulation piece 294. The timer 256 then controls the cylinder 272 towithdraw the stop 274. The timer 256 then controls the cylinders 258 and260 to move the frame 262 into position placing the spray heads 296 and298 surrounding and in alignment with the insulation piece 294 forspraying the top and bottom thereof. The spray heads 296 and 298 areprovided with the same foam forming components from the mixers 321 and323 as is supplied by the mixer 169. The mixer 321 is supplied withcomponent A through the conduit 325 and the resin component B throughthe conduit 327. The mixer 323 is supplied with the component A throughthe conduit 329 and the resin component B through the conduit 331.

6 Suitable spray heads corresponding to the spray heads 296 and 298 areprovided in position to spray all the upright edges of the insulationpiece 294 so as to enclose the gas within the insulation piece 294.

After this spraying is completed and the supply to the spray heads iscut off by the timer 256, the timer controls the cylinders 258 and 260so as to place the infrared heaters 333 and 335 in alignment with theedges of the insulation piece 294 to supply heat to complete the foamingand the curling of the foam forming materials deposited on the edges ofpiece 294. After the spray deposited foam material is cured, the timer256 controls the cylinders 253 and 260 to move the framework 262 to theleft out of the path of the insulation piece 294. Thereafter thecylinders 286 and 288 are operated by the timer 256 to move the plates290 and 292 away from the piece 294 to allow it to fall through theoutlet chamber 337 provided with the sidewalls 339 and 341 as well asthe double trap doors 343 and 345. The trap doors 343 and 345 arenormally spring held in the closed position tightly so that when theinsulation piece 294 falls, it will first open and close the upper trapdoor 343 and then it will push open the lower trap door 345 after theupper trap door 343 has reclosed. The atmosphere within the chamber 236is charged with the gas having the low coefficient of heat transmissionfrom a storage. tank 347 through the pipe 349 under the control of ashutoff valve 351 and a constant pressure outlet valve 353 whichdischarges through the pipe 355 into the chamber 230 so as to keep thechamber 230 filled with the gas at a slight pressure. This will supplyor replace the gas which is taken out of the chamber in the insulationpieces and also compensates for any leakage at the inlet and the outlet.

The flexible closed cell substantially impervious foam polymer whichsurrounds the outside of both forms of insulation pieces not onlyprevents the escape of the gas within the insulation core but it is alsoan excellent insulation material in itself. It is sufficiently durableand flexible to withstand normal handling and usage in processing andpacking and installing in the structure to be insulated. In the firstform it effectively prevents the film from being punctured during thelater portions of the processing and handling. The flexible polymer alsoaids in providing a close fit within a confined space, thus eliminatingair pockets. It also is sufliciently flexible to permit expansion andcontraction of the gas having the low coeflicient of heat transmissionunder variations in temperature and barometric pressure While preventingits escape or the ingress of air and while preventing the formation ofair pockets within such a confined space outside the flexible polymer.

If a more rigid external envelope is desired, a polyetherurethane foamof the closed cell type containing the same insulating gas may be usedif desired.

While the embodiments of the present invention as herein disclosedconstitute preferred forms, it is to be understood that other formsmight be adopted.

What is claimed is as follows:

1. The method of making insulation which includes squeezing out a majorportion of the gas in a permeable resilient material containing a gasand replacing said gas with a second gas having better insulatingproperties as the resilient material reexpands, and while retaining theinsulating gas in said resilient material applying a sealing coatingcompletely around said resilient material suificient in amount to sealin the gas having the better insulating properties.

2. The method of making insulation which includes squeezing out a majorportion of the gas in a permeable resilient material containing a gasand replacing said gas with a second gas having better insulatingproperties as the resilient material reexpands, and While retaining theinsulating gas in said resilient material applying materials forming aclosed cell foamed polymer completely around said resilient materialsuflicient in amount to seal in the gas having the better insulatingproperties.

3. The method of making insulation which includes squeezing out a majorportion of the gas in a permable resilient material containing a gas andreplacing said gas with a second gas having better insulating propertiesas the resilient material reexpands, and while retaining the insulatinggas in said resilient material applying materials forming a closed cellfoamed polymer also containing a gas having good insulating propertiescompletely around said resilient material sufficient in thickness toseal in the gas having the better insulating properties.

4. The method of making insulation which includes applying a sheet of aflexible material to a resilient insulating material containing a gas,squeezing a major portion of the gas out of said insulating material andreplacing the gas with a second gas having better insulating properties,and sealing said sheet of flexible material to completely enclose saidinsulating material to keep the second gas in the insulating materialand to exclude other fluids.

5. The method of making insulation which includes applying a sheet of aflexible material to a resilient insulating material containing a gas,squeezing a major portion of the gas out of said insulating material andreplacing the gas with a second gas having better insulating properties,and sealing said sheet of flexible material to completely enclose saidinsulating material to keep the second gas in the insulating materialand to exclude other fluids, and applying to the completed sheetenclosure materials forming a closed cell foamed polymer.

6. The method of making insulation which includes applying a sheet of aflexible material to a resilient insulating material containing a gas,squeezing a major portion of the gas out of said insulating material andreplacing the gas with a second gas having better insulating properties,and-sealing said sheet of flexible material to completely enclose saidinsulating material to keep the second gas in the insulating materialand to exclude other fluids, and applying to the completed sheetenclosure materials forming a closed cell foamed polymer also containinga gas having good insulating properties.

7. The method of making insulation which includes feeding a strip ofresilient insulating material containing a gas, squeezing the insulatingmaterial as it is fed to squeeze out a major portion of said gas,introducing into the insulating material as it reexpands a second gashaving better insulating qualities, applying to the insulating materialafter reexpansion materials forming a closed cell foamed polymersuflicient in amount to seal in the second gas, cutting the strip intolengths, and applying to the cut portions of the strip materials forminga closed cell polymer suflicient in amount to complete the scaling in ofthe second gas.

8. The method of making insulation which includes feeding a strip ofinsulating material containing a gas, applying sheet material toopposite faces of said strip, squeezing the sheet and insulatingmaterial to squeeze out a major portion of the gas and sealing edgeportions of the sheet, introducing into said insulating material asecond gas having better insulating qualities as said insulatingmaterial reexpands to charge the interior of the enclosure provided bythe sheet material with said second gas, transversely sealing the sheetmaterial as spaced intervals and cutting the sheet material at thelocations where the sheet is transversely sealed.

9. The method of making insulation which includes feeding a strip ofinsulating material containing a gas, applying sheet material toopposite faces of said strip, squeezing the sheet and insulatingmaterial to squeeze out a major portion of the gas and sealing edgeportions of the sheet, introducing into said insulating material asecond gas having better insulating qualities as said insulatingmaterial reex'pands to charge the interior of the enclosure provided bythe sheet material with said second gas, applying to the exterior of thesheet materials forming a closed cell foamed polymer which issubstantially impervious to said second gas, transversely sealing thesheet material at spaced intervals and cutting the sheet material at thelocations where the sheetis transversely sealed.

10. Apparatus for making resilient insulation containing a gas havinggood insulating properties which includes means for squeezing a firstgas out of resilient insulation and then reducing the squeezing of theinsulation, means for introducing a second gas having better insulatingproperties into the insulation as the squeezing is reduced, and meansfor applying liquid foam forming materials around said resilientinsulation to seal in the second gas within the resilient insulation.

11. Apparatus for making resilient insulation containing a gas havinggood insulating properties which includes means for squeezing a firstgas out of resilient insulation and then reducing the squeezing of theinsulation, means for introducing a second gas having better insulatingproperties into the insulation as the squeezing is reduced, means forenclosing said resilient insulation in a bag, means for sealing the bag,and means for coating the bag with liquid foam forming materials.

12. The method of making insulation which includes applying protectorsheeting to the opposite sides of a permeable resilient material,squeezing the protector sheeting together to squeeze out a major portionof the gas from the resilient material containing the gas and replacingthe gas squeezed out by a second gas having better insulating propertiesas the resilient material reexpands, and while retaining the second gasin said resilient material applying a sealing coating completely aroundsaid protector sheeting and resilient material.

13. The method of making insulation which includes applying protectorsheeting to the opposite sides of a permeable resilient material,squeezing the protector sheeting together to squeeze out a major portionof the gas from the resilient material containing the gas and replacingthe gas squeezed out by a second gas having better insulating propertiesas the resilient material reexpands, and While retaining the second gasin said resilient material enclosing said protector sheeting andresilient material in a sheet material and sealing said sheet material.

14. The method of making insulation which includes applying protectorsheeting to the opposite sides of a permeable resilient material,squeezing the protector sheeting together to squeeze out a major portionof the gas from the resilient material containing the gas and replacingthe gas squeezed out by a second gas having better insulating propertiesas the resilient material reexpands, and while retaining the second gasin said resilient material enclosing said protector sheeting andresilient material in a sheet material and sealing the sheet material,and then applying to the exterior of the sheet material materialsforming a closed cell foamed polymer.

References Cited by the Examiner UNITED STATES PATENTS 543,964 8/95Michell 154-451 1,637,547 8/27 Brown 154-45.l 1,978,041 10/34 Dodge156-79 2,244,097 6/41 Burkart 156-281 XR 2,599,625 6/52 Gilman 156-3832,863,179 12/58 Gaugler 161-407 XR 2,879,197 3/59 Muskat et al. 156-792,955,971 10/60 Irwin 156-79 3,004,877 10/61 Simms 156-145 XR 3,009,29811/61 Gerlach et al. 53-22 EARL M. BERGERT, Primary Examiner.

1. THE METHOD OF MAKING INSULATION WHICH INCLUDES SQUEEZING OUT A MAJORPORTION OF THE GAS IN A PERMEABLE RESILIENT MATERIAL CONTAINING A GASAND REPLACING SAID GAS WITH A SECOND GAS HAVING BETTER INSULATINGPROPERTIES AS THE RESILIENT MATERIAL REEXPANDS, AND WHILE RETAINING THEINSULATING GAS IN SAID RESILIENT MATERIAL APPLYING A SEALING COATINGCOMPLETELY AROUND SAID RESILIENT MATERIAL SUFFICIENT IN AMOUNT TO SEALIN THE GAS HAVING THE BETTER INSULATING PROPERTIES.
 10. APPARATUS FORMAKING RESILIENT INSULATION CONTAINING A GAS HAVING GOOD INSULATINGPROPERTIES WHICH INCLUDES MEANS FOR SQUEEZING A FIRST GAS OUT OFRESILIENT INSULATION AND THEN REDUCING THE SQUEEZING OF THE INSULATION,MEANS FOR INTRODUCING A SECOND GAS HAVING BETTER INSULATING PROPERTIESINTO THE INSULATION AS THE SQUEEZING IS REDUCED, AND MEANS FOR APPLYINGLIQUID FOAM FORMING MATERIALS AROUND SAID RESILIENT INSULATION TO SEALIN THE SECOND GAS WITHIN THE RESILIENT INSULATION.